Testing of well packers



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Oct. 23, 1962 w. c. LlNDsEY TESTING OF WELL PACKERS 5 Sheeizs-Sheeil 1 Filed April 25. 1960 INVENTOR. WILLIAM C. LNDSEY,

fb 6- M ATTORNEY Oct. 23, 1962 Filed April 25, 1960 W. C. LlNDSEY TESTING OF WELL PACKERS 3 Sheets-Sheet 2 FIG.5.

IN VEN TOR.

WILLIAM C. LINDSEY,

ATTORNEY.

Oct. 23, 1962 w. c. LlNDsEY TESTING oF WELL PACKERS 3 Sheets-Sheet 3 Filed April 25, 1960 FIG. 6.

IIO

ATTORNEY United States Patent 3,059,696 TESTING 0F WELL PACKERS William C. Lindsey, Houston, Tex., assignor, by mesne assignments, to Jersey Production Research Company, Tulsa, Okla., a corporation of Delaware Filed Apr. 25, 1960, Ser. No. 24,572 4 Claims. (Cl. 166-4) This invention relates generally to the recovery of hydrocarbons from a plurality of hydrocarbon containing earth formations traversed by a well, and more particularly to the testing of packers on a pipe string separating a plurality of hydrocarbon containing earth formations in iluid communication with the interior of the pipe string.

On occasion it will be found feasible to sequentially produce a plurality of productive hydrocarbon containing earth formations through a single pipe string. Usual-ly it is necessary to isolate the hydrocarbon containing earth formations from each other with well packers aiiixed to the exterior of the pipe string so that production can be limited to a single productive earth formation at any given time. To this end it will be found necessary to test the effectiveness of the packers to insure that the packers are not leaking.

Furthermore, from time to time -governmental regulatory agencies permit oil tiel-d operators to transfer the monthly allowable production of a well to a second well in the same oil eld so that the second well, in effect, produces the allowable monthly production for both wells. In such instances the regulatory agency requires that, if a single production pipe string is used, the packers separating the productive earth formations be periodically tested for leakage.

The present invention contemplates that a single production pipe string penetrates a plurality of productive earth formations in a well, at least two of which formations are to be in fluid communication with the interior of the production pipe string. All except one of the formations are then fluidly isolated from the interior of the pipe string and the static iiuid pressure exerted by each of the isolated formations on the pipe string is measured. The one formation remaining in fluid communication with the interior of the pipe string is then produced, preferably for a time interval of at least 3 hours and the pressure exerted on the other formations is continuously meas ured and recorded. Any decrease in the measured pressure is indicative of a defective packer seal.

The objects and features of the invention will be better understood upon consideration of the following description taken in connection with the accompanying drawings, wherein:

FlG.`l is an elevational View, partially in cross-section, of pressure monitoring apparatus suitable for use in connection with the invention;

FIGS. 2, 3, 4, and 5 are views, partially in cross-section, of a portion of a well in the earth for the purpose of illustrating various steps involved in the practice of the invention;

FIG. 6 is an elevational view, partially in cross-section, of another type of apparatus useful in the practice of the invention; and

FIGS. 7 and 8 are views of a Well wherein the apparatus of FIG. 6 is used in the practice of the invention.

With reference now to FIG. l, the reference numeral 1 designates the housing of an elongated sonde or apparatus for sealing off a port in a tubing string, and for measuring fluid pressure exerted on the exterior of the tubing string in the vicinity of the port. A conventional fishing neck 3 is included at the upper end of the housing 1. Within the housing is apparatus for measuring and recording pressure variations. The apparatus includes a 3,059,696 Patented Oct. 23, 1962 strip chart 11 affixed to a chart drum 9 and rotationally driven by the output shaft 7 of a spring-driven clock motor 5. The clock motor may -be adapted to turn the chart 9 through one revoluti-on during a predetermined time interval which may be between one and three hours. Shaft 15 supports a stylus 13 operatively arranged with respect to the chart so that longitudinal movement 0f the stylus across the chart will produce a record on the chart indicative of -the longitudinal excursion of the stylus. A piston 31 is aifixed to shaft 15 at the opposite end of the shaft from the stylus. Shaft 15 extends through a partition 14, and a spring member 19 biases the shaft .'15 so that normally the stylus 13 is at one longitudinal extremity of chart 11. An O-ring or other suitable sealing device is used to provide a seal between the chamber 17 within which piston 31 moves, and the piston. A plurality of ports 35 are uidly connected to the piston chamber 17 by means of a passageway 33 so that pressure exerted therethrough forces piston 31 upwardly, thereby moving stylus 13 longitudinally across chart 11. Chevron seals 37 and 39 are provided above and below the ports 35.

With reference now to FIGS. 2, 3, and 4, there is shown in each gure a portion of a well having a casing 45 cemented to the earth formations therearound and perforated so as to be in fluid communication with a plurality of productive earth formations 41, 42, and 43. An elongated pipe string or tubing 44 is arranged within casing 45 and co-extends therewith from the earths surface. Packer members 47, 60, and are aiiixed to the exterior o-f the tubing string between the productive earth formations 41, 42, and 43 and immediately above earth formation 41. lt is assumed in the drawing that there is another productive earth formation (not shown) above earth formation 41 which is in fluid communication with the annulus of the pipe string. The pipe string 44 is provided with a pair of side pocket mandrels 51 and 57. The side pocket mandrels 51 and 57 respectively have ports 53 and 59 therein so that the interior of the pipe string may be placed in Huid communication with the earth formations 41 and 42, respectively, through the perforations in the casing. The side pocket mandrels are of the type ordinarily used in gas lift operations and will not be fur-ther described herein. Near the bottom end of the tubing string is a landing nipple 64 such as is ordinarily used in permanenttype well completion techniques. Ear-th formation 43 is in fluid communication with the interior of the pipe string through the lower end of the pipe string.

To test the packers 47 and 60 for leakage, the apparatus described in FIG. 1 is lowered into the pipe string after the clock motor 5 has Ibeen wound, and is manipulated into place in the side pocket mandrel 57 until seals 37 and 39 are respectively above and below port 59 so as to seal port 59 from iluid communication with the interior of the pipe string. A plug 63 is landed in the landing nipple 64 to prevent fluids from formation 43 from entering the interior of the pipe string 44. A suitable pressure measuring device may be connected at the well head t0 the annulus around the pipe string. Productive formation 41 is thereupon produced. After a time interval of at least 3 hours, production of formation 41 is stopped and the apparatus 61 is retrieved by means of a suitable fishing tool and wireline apparatus in the usual manner for gas lift devices. At the earths surface the pressure recordations are inspected to determine whether or not the packers 47 and 60 are leaking.

An apparatus 66 similar to that shown in FIG. 1 is then landed in landing nipple 64 as shown in FIG. 3, and a similar apparatus 62 is landed in side pocket mandrel 51. Productive earth formation 42 is thereupon produced. The pressure readings obtained with the apparatus 62 and 66 are compared after the apparatuses are retrieved from the well. In this manner packers 60 and 65 are tested for leakage.

Referring now to FIG. 4, sealing and pressure measuring apparatus 62 and 61 are then manipulated into the side pockets 51 and 57, respectively, and formation 43 is produced. This will provide a positive check of the sealing effectiveness of packer 65. However, this step may be eliminated if desired.

FIG. 5 illustrates an alternative method of testing the topmost packer member 60 when formation 41 is the topmost productive formation penetrated by the borehole. The sonde is landed in the mandrel adjacent formation 42, and formation 41 is produced through the annulus. A plug 63 is landed in the landing nipple 64. The sonde 62 -is retrieved and the pressure record examined to determine the sealing effectiveness of packer 60.

In FIG. 6 there is shown a pipe string 93 including a mandrel 86 having a plurality of ports 85 therein. The mandrel 86 has a somewhat greater inside diameter than the inside diameter of the rest of the tubing string so as to accommodate a sliding sleeve 99 that has substantially the same inside diameter as the inside diameter of the tubing string. The sliding sleeve 99 is provided with a port 96 that may be aligned with ports 85 so as to provide fluid communication between the inside and outside of the pipe string 93. When the sleeve 99 is slid upwardly a sufficient distance, the ports 85 are sealed from the interior of the pipe string. The mandrel 86 is provided with locking recesses 97 and 98 for purposes to be described below. A pressure measuring sonde 69 is provided which is similar in certain respects to the sonde described with reference to FIG. l. The sonde has a fishing neck 68 to which may be afixed a suitable fishing head at the end of the wireline in the usual manner. The sonde is provided with a clock motor 71, a chart drum 72, chart 73, stylus 75, stylus shaft 77, piston S1, and coil spring 79, substantially identical with similar components described in FIG. 1. The lower end of the piston chamber 80l is in fluid communication with the exterior of the sonde through `a suitable passageway 83.

Sealing members 91 and 95, which may be chevron seals or packers, are aixed to the exterior of the sonde above and below the ported passageway 83. The sealing members 91 and 95 are adapted to provide a fluid seal between the sonde and the sliding sleeve 99 so that the ported passageway 83 is in fluid communication with the port 96 provided in the sliding sleeve 99. For the purpose of locking the sonde into the sliding sleeve, the sliding sleeve 99 is provided with an annular recess -107 and an annular shoulder 111. Shoulder 111 abuts against the tapered upper end 109 of nipple 110 when the sleeve 99 is in its lowermost position, A split ring locking member 101 is provided within the ange and is adapted to engage the locking recesses 97 and 98. Downwardly facing dogs 100 and upwardly facing dogs 105 are hingedly aixed to the sonde and are adapted to extend therefrom. The dogs are used in conjunction with a locking and shifting mechanism 103 which may be substantially identical to the locking and shifting mechanism associated with the type S gas lift valve manufactured by Garret Oil Tool Company and described at page 1901 of the Composite Catalog of Oil Field and Pipe Line Equipment, 21st ed. (1955). The locking mechanism is adapted to be actuated by standard wireline fishing tools and jars. It is designed so that it will pass into the mandrel into which it is to be installed, and after passing into the mandrel, it is raised until the upward facing dogs 105 engage the annular shoulder 111 of the sleeve 99. Additional upward strain frees the downward facing dogs which then engage in the upper recess 107, thus locking the sonde against movement in either direction with respect to the sleeve 99. Downward jarring with the wireline equipment on the sonde then moves the sleeve 99 and sonde 69 until the port A96 is adjacent ports 85 so that fluid pressure exerted through ports 85, port 96, and passageway 83 will force piston 81 upwardly to provide a pressure record on chart 73. 'Ihe sonde may then be retrieved by jarring the sonde upwardly which first closes the sleeve valve and shears a pin within the locking and shifting tool 103 to free the upward facing dogs 105. The dogs are retracted into the locking and shifting tool 103 by this action and are held retracted by a spring within the locking and shifting tool so that the entire sonde may be lifted from the mandrel.

A passageway 106 is provided which extends through the locking and shifting tool portion of the sonde, up past the tubular member 84, the housing yfor passageway 83, and terminates in ports 87 so that uid may pass from the pipe string below the sonde up through the sonde, and around the upper portion of the sonde to the portion of the pipe string above the sonde.

FIGS. 7 and 8 illustrate the manner in which sonde 69 is used to test packers 47 and 60. The sonde is lowered into the well on the end of a wireline until it is seated in the mandrel adjacent productive formation 41. Ports a and 96a are brought into registry in the manner described above so that the earth formation 41 is in fluid communication with the piston 81 (see FIG. 6) of the sonde. The sliding valve mandrel adjacent productive formation 42 remains closed, with ports 96b and 85b out of registry. Earth formation 43 may be produced during the time that packer 47 is being tested since uids will flow through the sonde without affecting the operation of the pressure measuring components of the sonde. The clock motor 71 of the sonde is wound at the earths surface and the sonde is seated in the mandrel adjacent formation 41 to measure pressure in earth formation 41 without producing the formation 40 for a time interval suicient to allow subsurface Huid conditions in the formations 40 and 41 to stabilize. Productive formation 40 is thereupon produced for a time interval of at least 3 hours and a pressure record is made of the static pressure exerted by formation 41 on the pipe string 44 during the entire interval. The sonde is then retrieved by a suitable wireline fishing device, and the record is removed. Another sonde is lowered into the pipe string as shown in FIG. 8 and seated in the mandrel adjacent formation 42. The sliding sleeve 99b is slid downwardly so as to bring ports 85b and 96b into registry as shown in FIG. 8. A wireline tool substantially the same as the Garrett Oil Tool type B-3 sleeve shifting tool illustrated at page 1905 of the Composite Catalog of Oil Field and Pipe Line Equipment, 21st ed., is thereupon lowered into the well to open the sliding valve adjacent formation 41 by bringing ports 85a and 96a into registry. A plug 63 is inserted into landing nipple 64 prior to running the sonde in order to plug olf the lowermost formation 43, as shown in FIG. 8. As soon as subsurface formation conditions have stabilized, formation 41 is produced for a time interval of at least 3 hours, and thereafter the sonde and plug are retrieved from the well.

A similar sequence of operations is used to test packer 65: Plug 63 may be removed and the sliding valve adjacent formation 41 may be closed. The sonde may agam be seated adjacent formation 42, and formation 43 may be produced through the sonde. The pressure records obtained as described above are inspected to ascertain whether or not there is a pressure drop after the formations have been produced. A drop in pressure is indicative of a leaking packer and it may be necessary to pull the pipe string 44 to replace one or more of the packers should a leaking condition be detected.

The invention is not to be restricted to the specific structural details, arrangement of parts, or circuit connections herein set forth, as Various modifications thereof may be effected without departing from the spirit and scope of this invention.

What is claimed is: j

1. In a well including a pipe string having openings therein to provide fluid communication Awith a plurality of hydrocarbon containing earth formations and having packer means affixed to the exterior of the pipe string for preventing uid communication between the hydrocarbon containing earth formations through the well annulus around the pipe string, the mgthogdggimdggting leakage past said packer means comprising: producing one of said earth formations; and measuringlariations in the stati-ppessme exerted on the well pipe at said openings by hydrocarbon containing earth formations adjacent the produced formation before and during the time interval over which said one earth formation is being produced.

2. In a well including a pipe string having openings therein for iuid communication with a plurality of hydrocarbon containing earth formations and having packer means affixed to the exterior of the pipe string for preventing fluid communication between the hydrocarbon containing earth formations through the well annulus around the pipe string, the method of detecting leakage past said packer means comprising: closing selected openings in the pipe string to prevent fluid iiow into the pipe string from all but one of the hydrocarbon containing earth formations; producing said one of said earth formations; and measuring variations in the static pressure exerted on the well pipe at said openings by the hydrocarbon containing earth formations adjacent said one earth formation before and during the time interval over which said one earth formation is being produced.

3. In a well including a pipe string having openings therein to provide uid communication with a plurality of hydrocarbon containing earth formations and having packer means aixed to the exterior of the pipe string for preventing fluid communication between the hydrocarbon containing earth formations through the well annulus around the pipe string, the method of detecting leakage past said packer means comprising: closing selected openings in the pipe string to prevent fluid flow into the pipe string from all but one of the hydrocarbon containing earth formations; producing said one of said earth formations; and continuously measuring variations in the static pressure exerted on the pipe string at said openings by the hydrocarbons containing earth formations adjacent said one formation before and during production of said one earth formation for a period extending to at least 3 hours after initiation of production.

4. In a well including a pipe string in uid communication with a plurality of hydrocarbon containing earth formations through openings in recesses in the pipe string, said recesses being out of the iiow path of fluids through the pipe string, said pipe string having packer means affixed thereto for preventing uid communication between the hydrocarbon containing earth formations through the well annulus surrounding the pipe string, the method of testing the packers comprising: blanking off the openings in the recesses adjacent the productive earth formations adjacent one of the formations by inserting a pressure measuring and recording device in the recesses to be blanked off, adapted to measure and record pressure variations in the blanked oif formations; and producing said one formation for at least 3 hours while continuously measuring and recording variations in the pressure in the blanked off formations before and after initiation of production.

No references cited. 

